Just wanted to point out that the article you reference says 660k listings in the US, not hosts. I was initially concerned by your wording that the number of properties for rent on Airbnb was much higher (since often hosts have multiple properties, or the host is listed as a management company), but it does seem that 660k is the number of listings.

And I agree with you that number is much lower than I would have expected, and doesn't seem like enough to meaningfully move housing prices overall. Also consider that some number of those listings are people renting out a spare room in their owner-occupied property, which I don't think is fair to count "against" Airbnb; not sure what that number is, though.

It would be interesting to also see more local numbers. Like what percent of units in each of SF, NYC, downtown LA, Chicago, DC, etc. are listed on Airbnb? There are a lot of housing units in small towns and cities across the US that don't have much tourist appeal, so they likely don't see many Airbnb listings. But they also likely don't have housing-cost issues like some cities that are more attractive to tourists.

I think people try to invent complicated reasons for skyrocketing home prices, when it's fairly simple: we aren't building enough in the places where people want to live. Sure, other things (Airbnb, foreign investment[0], cheap credit, etc.) don't help matters, but I think they're pretty minor factors. If there's demand, and you don't meet it, prices go up. Econ 101.

It's interesting to note that Vancouver and Toronto instituted 20% and 15% (respectively) foreign buyer taxes for home purchases a bunch of years ago. These taxes did actually do their job of deterring foreign buyers, but, sadly, home prices still continued to go up, undeterred. And now Canada overall has barred foreign buyers for two years. I doubt it will help. I expect Airbnb bans would have a similar non-effect.